in this research, tribological characteristics of ni-p electroless coating and double-layered ni-p/ni-b electroless coating were studied. for this purpose, ni-p electroless coating with 25 μm thickness was initially applied to the surface of steel ck45 samples; then, a double-layered ni-p/ni-b electroless coating, including inner layer of ni-p with 15 μm thickness and outer layer of ni-b with 1...

a series of tialon coatings were synthesized in a gaseous mixture of argon, nitrogen and oxygen by cathodic arc evaporation method using a ti–al mosaic target. oxidation of coatings was carried out by heating the coated samples at the temperatures of 500, 600, 700, and 800°c for 1 h in air atmosphere. it was found that heat treatment changed the microstructure and composition of the coating. th...

despite having some useful properties, stainless steels suffer from lack of suitable surface hardness. in this research electroless ni-b-tl coating was used with the aim to increase their surface hardness. the effects of nickel chloride, sodium borohydride, thallium nitrate and ethylendiamin on the chemical composition of coating were studied. to achieve an increase in hardness, the effects of ...

A series of TiAlON coatings were synthesized in a gaseous mixture of argon, nitrogen and oxygen by cathodic arc evaporation method using a Ti–Al mosaic target. Oxidation of coatings was carried out by heating the coated samples at the temperatures of 500, 600, 700, and 800°C for 1 h in air atmosphere. It was found that heat treatment changed the microstructure and composition of the coating. Th...

In this research, tribological characteristics of Ni-P electroless coating and double-layered Ni-P/Ni-B electroless coating were studied. For this purpose, Ni-P electroless coating with 25 μm thickness was initially applied to the surface of steel Ck45 samples; then, a double-layered Ni-P/Ni-B electroless coating, including inner layer of Ni-P with 15 μm thickness and outer layer of Ni-B with 1...

in this investigation, fluor-hydroxyapatite (fha) film was deposited on a titanium substrate by sol-gel method. triethyl phosphite, ammonium fluoride and calcium nitrate in ethanol solutions were used respectively as p, f and ca precursors. typical apatite structures were obtained for all coatings after dipping and subsequent heat treatment at 550, 700 and 800 ºc, the coating layers were invest...

Abstract: Two different coating microstructures of Ni-50Cr alloy were obtained on a stainless steel substrate by changing combustion characteristics of a high velocity oxy-fuel (HVOF) process and the size distribution of feed powder during coating process. Use of the finer feed powder and leaner fuel in oxygen/fuel ratio (i.e. using a ratio much less than stoichiometric ratio) led to formati...

low water-wettability and oxidation resistance of graphite have limited its application in carbon containing refractory castables. the aims of this study were improvement of water-wettability and the oxidation resistance of natural flaky graphite by applying an oxide coating on its surface. to develop the coating, magnesium aluminate spinel sol was formulated via a citrate-nitrate route and gra...